1. Field of the Invention
The present invention relates to an apparatus for precisely driving X-Y stages using a VCM (Voice Coil Motor) precisely moving to XY axes, and more particularly, to an apparatus for precisely driving X-Y stages using a VCM and elastic member precisely moving to XY axes, magnetic force generators of which are connected to the upper portions of a stage which is movable in a direction of Y-axis and a stage which is movable in a direction of X-axis, thereby performing a biaxial movement smoothly without interference in mutual movement of stages when the stages move in a movement direction of power.
2. Background of the Related Art
In general, a PZT (Piezoelectric Transducer) is widely used as XY stages for transferring a specimen on a microscope in a micro field. However, because a movement amount of the PZT is restricted to 1 nmxcx9c10 xcexcm, it can be amplified just up to several tensxcx9cseveral hundreds xcexcm even though a structure of an amplifier is changed.
Furthermore, a system of the stage becomes complex because the amplifier structure is used. If a user wants to move to a stroke of several centimeters, a driving apparatus is needed additionally.
Moreover, if a motor and a linear guide (a ball bearing, a ball screw, or the likes) are used, there is problem in movement of a long stroke, but there is a limit in precision due to friction. At this time, the limit is about 100 nm. However, there is a movement, which falls short of the user""s expectations, in a horizontal direction to a plane movement.
Next, an air bearing guide and a linear motor may be used. In this case, the PZT can move to a long region of several tens nm to several hundreds xcexcm. However, it has a large and complex structure, and causes a vertical movement regardless to the plane movement by the air bearing so as to need an additional driving stage capable of causing the vertical movement.
Accordingly, the present invention is directed to an apparatus for precisely driving X-Y stages using a VCM (Voice Coil Motor) and elastic member that substantially obviates one or more problems due to limitations and disadvantages of the related art.
An object of the present invention is to provide an apparatus for precisely driving X-Y stages using a VCM, which does not include any movement directions different from a desired direction, has a symmetric structure stable to a thermal change, and performs biaxial movement easily.
Another object of the present invention is to provide an apparatus for precisely driving X-Y stages using a VCM, which includes X and Y axis stages of the same structure, each of which has a part driving on both fixed sides and a part connected to the driving part by an elastic member and driving in the same direction as the driving part, and magnetic force generators connected to the stages respectively for providing the stages with driving force.
In order to achieve the above objects, there is provide to an apparatus for precisely driving X-Y stages using a VCM (Voice Coil Motor) according to the present invention, comprising: (a) a frame have a bottom with a predetermined size and shape and side walls surrounding the bottom with a predetermined height; (b) a first stage movable in a first direction with respect to a horizontal plane, including: a first magnet assembly fixed to on a bottom of the frame; a first force generating unit movably connected to the first magnet assembly, wherein the first force generating unit moves in the first direction with respect to the first magnet assembly according to a first current applying thereto; and first elastic members guiding the first force generating unit to the first direction and returning its normal position, the elastic members are fixed to the first force generating unit; (c) a second stage movable in a second direction orthogonal to the first direction with respect to the horizontal plane, including: a second force generating unit fixedly installed onto the first force generating unit, where the second force generating unit is aligned to moves orthogonally to the movement direction of the first force generating unit; a second magnet assembly movably connected to the second force generating unit, the second magnet assembly moves in the second direction with respect to the second force generating unit according to a second current applying thereto; and second elastic members guiding the second force generating unit to the first direction and returning its normal position with respect to the second magnet relatively moving to the second force generating unit; and (e) a specimen transferring part fixedly installed to the second magnet.
Additional advantages, objects, and features of the invention will be set forth in part in the description which follows and in part will become apparent to those having ordinary skill in the art upon examination of the following or may be learned from practice of the invention. The objectives and other advantages of the invention may be realized and attained by the structure particularly pointed out in the written description and claims hereof as well as the appended drawings.
It is to be understood that both the foregoing general description and the following detailed description of the present invention are exemplary and explanatory and are intended to provide further explanation of the invention as claimed.